Methylomonas

Abstract

Me.thy.lo.mo'nas . N.L. pref. methylo‐ pertaining to the methyl radical; L. fem. n. monas unit; N.L. fem. n. Methylomonas methyl monad or methyl unit. Proteobacteria / Gammaproteobacteria / Methylococcales / Methylococcaceae / Methylomonas Straight or slightly curved rods 0.5–1.1 × 0.5–4.0 µm, occurring singly, in pairs, or in short chains. Some species form a polysaccharide‐containing cyst that is desiccation sensitive. Some species are motile by means of a single polar flagellum . Gram‐negative. Most species have a strictly aerobic respiratory metabolism , with oxygen as the electron acceptor. Obligate utilizers of methane and methanol for carbon and energy . No growth occurs on carbon–carbon‐bonded compounds. Some members of the genus can couple denitrification and methane oxidation. Fix formaldehyde by the ribulose monophosphate pathway . Ribulose‐1,5‐diphosphate carboxylase activity is absent. Some species fix atmospheric nitrogen via an oxygen‐sensitive nitrogenase. Some species form red, pink, and orange carotenoid non‐water‐soluble pigments. Mesophilic , growing between 10 and 40°C, optimal growth temperatures 25–30°C. Nonhalophilic. Some species are nonhalotolerant. Major fatty acids include C 14:0 , C 16:1 ω8 c , C 16:1 ω7 c , C 16:1 ω6 c , C 16:1 ω5 c , C 16:1 ω5 t , and C 16:0 . 18‐Methyleneubiquinone‐8 (MQ‐8) is the predominant lipoquinone. Main polar lipids are phosphatidylglycerol and phosphatidylethanolamine. Habitat: Isolated from sediments of freshwater lakes and rivers, wetland muds, activated sludge and wastewater, coal mine drainage waters, and groundwater. DNA G +C content (mol%) : 47–59 ( T m , HPLC, genome sequences). Type species : Methylomonas methanica Whittenbury and Krieg 1984b, 355 VP (Effective publication: Whittenbury and Krieg 1984a, 260.)

Phylogenomic Analysis of the Gammaproteobacterial Methanotrophs (Order Methylococcales) Calls for the Reclassification of Members at the Genus and Species Levels

“…The same could be said for the inferred Methylomonas clade, the largest monophyletic clade formed by the majority of Methylomonas strains (Figure 2), which would be split into seven genera. It would separate Methylomonas methanica NCIMB 11130 T (Bowman, 2016b) and “ Methylomonas denitrificans ” FJG1 T (Kits et al, 2015) from Methylomonas koyamae JCM 16701 T (Ogiso et al, 2012; Supplementary Figure S3). On the other hand, this POCP threshold would merge Methylococcus capsulatus Texas T (Foster and Davis, 1966) and Methyloterricola oryzae 73a T (Frindte et al, 2017) into the same genus.…”

“…Tracking the original M. agile and M. album isolates is difficult since they were originally isolated and identified in 1970 (as Methylomonas agile and Methylomonas albus , respectively) (Whittenbury et al, 1970). Also, it is unfortunately common for methanotrophic isolates to be lost from or mis-deposited into culture collections, as these isolates take substantial efforts to maintain (Bowman, 2016b). Both strains are no longer available from the NCIMB (National Collection of Industrial Food and Marine Bacteria), where the strains were also initially deposited (Bowman et al, 1993, 1995).…”

“…Type strains M. methanica NCIMB 11130 T and “ M. denitrificans ” FJG1 T exhibit 92% dDDH and 100% ANI with each other, indicating that they should be considered as the same species (cluster 38) (Figure 2 and Supplementary Table S4). Both strains are pale pink, utilize flagella for motility, and are neutrophilic and mesophilic, which are characteristics of M. methanica (Kits et al, 2015; Bowman, 2016b). With “ M. denitrificans ” being described much later than M. methanica , the former name is proposed to be a later heterotypic synonym of the latter.…”

“…In cases were phenotypic information was needed to clarify taxon affiliation, data on several phenotypic characteristics commonly tested between organisms were collected from the original isolation papers and the Bergey’s Manual of Systematics of Archaea and Bacteria (Table 1; Bowman, 2016a,b; Hirayama, 2016; Kalyuzhnaya, 2016a,b; Collins et al, 2017; Bowman, 2018). Data missing from isolation papers and information on isolates that are not type strains were retrieved from other references as stipulated.…”

Network analysis uncovers associations in the turnover of C1 molecules in a winter lake

“…Under ice-cover, aerobic β-proteobacterial Rhodoferax OTU025, Polaromonas OTU011, and γ-proteobacterial Methylococcaceae OTU024 (Fig 2, grey circle Fig 3) dominated Lake Lomtjärnen surface waters. All three potentially contribute directly to C1 cycling and are also predicted to fix N 2 (Hanson et al ., 2012; Bowman, 2016; Baker et al ., 2017). Rhodoferax and Polaromonas are mixotrophs (Sizova and Panikov, 2007; Kato and Ohkuma, 2021; Taubert et al ., 2022), being able to both fix inorganic and use organic C for energy and biomass.…”